I was having trouble finding codes on my ls1 but I found the way and now I also found how to reset the light and to check airbag codes and other modules and to reset them.
You will need elm327 code scanner, I prefer elmscan5 compact usb. You will need proscan 5.9. In proscan 5.9 (note 5.7 version will not work) go to file then communication settings and set to automatic detect.
Then click connect.
Then go to the elm menu (it is a white box with elm written on it, next to the log button)
There will be a white box, In it you can type codes. There will be '01 01' already in it so erase that.
In the box copy paste 'AT SH 6C 10 F1' without brackets and hit enter or send. It should say OK. Next to retrieve the codes copy paste '19 d2 FF 00' without brackets and it will give the codes that are setting the check engine light on. To reset the light. Copy paste '14' without brackets in the box and enter and it will reset the Engine light. You will see the engine light go off and it will turn on again if it detects a fault. This will CLEAR ALL CODES/ RESET.
Note that in 'AT SH 6C 10 F1' the number 10 refers to the ecm/pcm. And '19 d2 FF 00' is the code to retrieve codes. '14' is to reset the light. Remember that you have to enter 'AT SH 6C 10 F1' enter and then '19 d2 FF 00' enter and then '14' enter in sequence to reset the ecu. To check codes for other modules here is the list:
28 ABS
40 BCM
10 ECM / PCM (Note: this was number 10 in 'AT SH 6C 10 F1')
58 Airbag
60 Instument Panel Cluster
80 Radio
C0 immobilizer
62 HUD
So lets see if you want to check the codes for airbag you have to enter 'AT SH 6C 58 F1'. (note that I replaced the 10 with 58 in the code). 58 in 'AT SH 6C 58 F1' refers to airbag. So to check codes enter 'AT SH 6C 58 F1' it should say OK. Then enter '19 d2 FF 00' it will give you all airbag codes. To clear the airbag code type in '14'.
Remember everytime you type in 'AT SH 6C 58 F1' it will talk to the airbag or whatever you put in there. So to talk to a different module for example the ABS, you have to type in 'AT SH 6C 28 F1'. You can clearly see that I replaced 58 with 28 for it to talk too the ABS iinstead of the Airbag. both 58 and 28 are in the list above where 58 refers to airbag and 28 refers to ABS.
Important, to retrieve codes from each module you type in 'AT SH 6C xx F1' where xx is the module number in the above list and then type in '19 d2 FF 00' to retrieve the codes form the specific module. And to reset the module type in '14' after you have retrieved the codes from that module.
So for me, when I typed in 'AT SH 6C 10 F1' followed by '19 d2 FF 00' I got
6cf110590523ff38 on the screen which means codes P0523. Note the code comes after 59. So in 6cf110590523ff38 the code is after 59. If there are no codes or end of list you will get No Data or 0000 after 59 in the code. After i check the code for ecm/pcm (the damn engine light) I typed in '14' and it reset the light and the light turned on again and gave me P0523 which means bad oil sensor. So now I know that I have bad oil sensor.